Office chair



FIG. 1 is a perspective view of an office chair showing my new design;

FIG. 2 is another perspective view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a left side elevational view thereof;

FIG. 6 is a right side elevational view thereof;

FIG. 7 is a top plan view thereof; and,

FIG. 8 is a bottom plan view thereof.

The broken lines in the drawings illustrate portions of the office chair that form no part of the claimed design. 

CLAIM The ornamental design for an office chair, as shown and described. 